#include <conio.h>
#include <stdio.h>
int tinhGT(int n){
	if( n == 0 || n == 1) return 1;
	int gt = 1;
	for( int i = 1; i <= n ; i++){
		gt *= i;
	}
	return gt;
}
int tinhGTDeQuy(int n){
	if( n == 0 || n == 1) return 1;
	else return tinhGTDeQuy(n-1) * n;
}
int main(){
	printf("%d", tinhGT(5));
	printf("\n%d", tinhGTDeQuy(0));
	getch();
}
